His parents （）him to enlist when he was seventeen.

单项选择题Being a foreigner, Cad did not （）to the joke.

A. appreciate
B. catch on
C. laugh
D. like

单项选择题Talks on climate change resumed in the German city of Bonn on July 16 to（）global warming.

A. foeus on
B. combat
C. settle down
D. sum up